How many servings does this recipe make?

This recipe makes 4 servings. You can adjust the portion size directly on this page.

What ingredients do I need for Peanut Cake Bars?

You need 11 ingredients. The key ingredients include: 1 package chocolate cake mix (regular size), 1/2 cup water, 1/3 cup butter, softened, 1 egg, and more.

Is Peanut Cake Bars suitable as baking & desserts?

Yes, Peanut Cake Bars falls under the Baking & Desserts category and is a great choice for this type of meal.

How do I store leftover Peanut Cake Bars?

Store in an airtight container at room temperature for up to 3–5 days. For longer storage, freeze for up to 3 months — no need to refrigerate or reheat.

Peanut Cake Bars Recipe

Name: Peanut Cake Bars
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 4 servings
Ingredients: 1 package chocolate cake mix (regular size); 1/2 cup water; 1/3 cup butter, softened; 1 egg; 3 cups miniature marshmallows; 1 package (10 ounces) peanut butter chips; 2/3 cup light corn syrup; 1/4 cup butter, cubed; 2 teaspoons vanilla extract; 2 cups crisp rice cereal; 2 cups salted peanuts

Bake this irresistible Peanut Cake Bars at home. Made with chocolate cake, water, butter and egg. Easy step-by-step instructions included.

This Peanut Cake Bars relies on simple, everyday ingredients such as water, butter, softened, egg and miniature marshmallows. It comes together quickly and makes 4 servings, at about 1626 kcal each. The step-by-step instructions below are written to be easy to follow, even on a busy day.

Whether you're rounding off a family dinner, bringing a treat to a gathering, or simply satisfying a sweet craving, this Peanut Cake Bars delivers. Serve it warm or at room temperature, and add a scoop of ice cream or a spoonful of whipped cream for an extra-special finish.

Updated Jun 30, 2026

Serves 4 Baking & Desserts

1626

kcal

Calories

Tips for the best results

Read through all the steps once before you start and measure out your ingredients first — it makes everything go more smoothly.
Preheat the oven fully and bake on the middle rack for the most even results.
Check for doneness a few minutes early — a toothpick in the center should come out with just a few moist crumbs.
Let it cool before slicing so it sets properly and holds its shape.
Store leftovers in an airtight container in the fridge and enjoy within a few days.

Variations & substitutions

Use a neutral oil or a plant-based spread in place of butter for a dairy-free version.

No specific allergen information. Please check the ingredient list for possible allergens.

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Peanut Cake Bars

Tips for the best results

Variations & substitutions

My Personal Notes

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